Keep a watch on jboss-development mailing list https://lists.jboss.org/mailman/listinfo/jboss-development where roadmaps are usually published.
And the schedule for AS6 is discussed here http://lists.jboss.org/pipermail/jboss-development/2010-September/016606.html
There is no production version of JBoss Application Server, there is only a community edition.
For production use Enterprise Application Platform, see http://www.jboss.com/products/platforms/application/.
Thank you Jaikaran and Carlo, much appreciated